Apparatus for handling fluids



June 23, 1953 E. w. HERTENSTEIN, JR 2,642,675

I APPARATUS FOR HANDLING FLUIDS Filed Sept. 30, 1950 2 Sheets-Sheet l FIJI...

INVENI'OR E. W HERTEN TE/MJR ATTORNEY Patented June 23, 1953 2,642,675 APPARATUS FOR HANDLING FLU IDS Edgar W. Hertenstein, J r., Dundalk, Md., assignor to Western Electric Company, Incorporated, New York, N. Y., a corporation of New York Application September 30, 1950, Serial No. 187,763

4 Claims.

This invention relates to apparatus for handling fluids, and more articularly to automatic apparatus for discharging fluids from vacuum systems used for drying cables and the like.

In the manufacture of lead sheath cables, the cable core is placed in a heated drying oven to remove any moisture from the insulation of the core before the sheath is applied. The oven is connected to a closed vacuum system including a vacuum pump which extracts the vaporized moisture from the oven, a condenser which condenses the moisture in the extracted gas and a tank which collects the condensed moisture. In the past, it has been the practice to stop the vacuum pump at periodic intervals and to open the vacuum system to drain the condensate from the tank. This procedure usually depended upon the vigilance of an operator, and resulted in losing the vacuum in the entire system each time the condensate was drained therefrom. In addition, this method of draining the vacuum system also is inherently dangerous in that it is possi- ;ble for the level of the condensate in the tank to build up to such a point that some of the condensate could be drawn into the vacuum pump and seriously damage the pump and its prime mover.

An apparatus embodying certain features of the invention may comprise a closed space having a portion designed to receive a moisture bearing article, means for creating a vacuum in the closed space to extract moisture bearing gas from the article, means for condensing the moisture in the gas as the gas travels from the :closed space to the vacuum creating means,

means for collecting the resulting condensate in .a portion of the closed space, means for disconnecting the condensate collecting portion from .the remainder of the closed space when a predetermined amount of condensate is collected therein, and means for draining the condensate from the disconnected portion while maintaining .a vacuum in the remainder of the closed space.

An object of the invention is to provide new and improved apparatus for handling fluids,

A further object of the invention is to provide new and improved automatic apparatus for dis- .charging fluids from vacuum systems used for drying cable cores and the like.

Other objects and advantages of the invention will appear from the following detailed description of a specific apparatus embodying certain features of the invention, when read in conjunction with the appended drawings, in which:

Fig. l is a schematic diagram of a vacuum Fig. 2 is a schematic wiring diagram showing a control circuit for the apparatus shown in Fig. 1.

Referring now tothe drawings, and more particularly to Fig. l, a reel I having a length of cable core ll wound thereon is positioned in an oven I 2 provided with a plurality of tubes |4I4 through which hightemperature steam from a supply (not shown) is passed to heat the oven to a desired temperature. A door [5 is provided on the end of the oven for making the oven airtight when the door is closed. It is' to be assumed that the cable core II contains a plurality of insulated conductors, and may contain several layers of paper tape served spirally around the composite core to separate the core from a lead sheath to be applied over the core. The paper covering of the core must be thoroughly dry before the lead sheath is applied in order to maintain its dielectric strength at a high value. The high temperature steam passing through the tubes raises the temperature of the oven to a point at which it vaporizes any moisture in the paper covering.

The oven I2 is connected to a vacuum system for extracting the vaporized moisture from the oven at a temperature lower than the boiling point of the moisture in the insulation. The vacuum system includes a vacuum pump l6 driven by a suitable electric motor I'l. When the pump I6 is operating, the moisture laden gas in the oven is extracted through a pipeline into a condenser 21 having a plurality of tubes 22-22 through which a cooling liquid such as water is circulated. As. the extracted gas passes through the condenser, the moisture in the gas condenses and the condensate and the gas pass through a pipe 23 to a receiver 25. The condensate and the gas separate in the receiver 25, with the condensate falling to the bottom of the receiver while the gas travels through a pipe 26 to an inlet valve 27 of the pump Hi. When the pump is operated by the motor l1, each stroke of its piston to theleft, as viewed in Fig. 1, draws'gas from the receiver into the pump, and each stroke of the piston to the right exhausts the gas through an exhaust valve 28 into the atmosphere. The condensate flows from the receiver through a manually, operable valve 30, a pipe 3| and a valve 32 operated by gig electric motor 33 into a metallic control tank The control tank 35 is provided Witha low ally operable valve M and a valve 42 operated by an electric motor 43. A valve 45, operated by an electric motor 46, connects the top of the tank 35 to a vent device 41. The valves .42 and 45 are held in their closed positions :by their respective motors as long as the level of the condensate is below the level of the high-level probe 35 to the vent 41, has a terminal I03 connected to the bus 55 in series with a normally open contact I04 of the relay 94 and the normally open contact I of the relay 84. A terminal I of the motor 46 is connected to the bus 55 in series with a normally open contact I06 of the relay 76. A terminal I01 of the motor 46 is connected to the bus" 5'6. The motor '43, which operates the drain valve 42, has a terminal IIO connected to the bus 55 in series with the normally open contact I04 of the relay 94 and the normally open contact I00 of the relay 84. A terminal II I of the motor 43 is connected to the bus 55 in series with the normally open contact I06 of the relay A terminal H2 of the motor 43 is connected'to the bus 56. The motors 33,

' 4 6 and 4.3 are provided with terminals H4, H5

31. The portions of the probes 36"and 31 which contact the condensate are insulated electrical-1y from the tank 35. The receiver 25 is provided th a p be 413 S a t the p es 6 andsso'as to be engaged by the condensate thecondensate reaches a pr d t r ned le e i he receiver; I

The motor-operated valves 32, 42 and 4 5 are control ed by t e Pro e 36 a d 31 and an as oiatd l l c n r l e i e 5 shown in Fla Th s fig re s a che ic wir dia ra "of a control apparatus which receives potential from s=55 an conne tedto a u ce f A. 0. potential (not showml 7 The probes 36 and '31 a e con e d le tri al to the control i 5 w ic de e nc ud a t ans rm .60 the primary windings of which are connected in parallel and across the busses 55 and 56. A secondary winding 6| of the transformer 60 is connected to a rectifier 62, which converts the A- 0 ote tial ene t d y the Winding 6| to all C. potential suitablefor energizing a coil 63=of a relay 65. A second secondary winding 66 of the transformer 60 has one side thereof connected directly to a terminal'G-I to which the probe "3;? is connected, and the other terminal thereof is connected to ground at I0. The tank 35 also is connected to the ground 10. The probe 36 is connected to the terminal .61 in series with a normally open contact 12 of the relay 65. An operating {coil :15 of a relay 16 is connected across'the busses 55 and 56 in series with a normally closed contact 11 of the relay 65.

An operating coil 80 of a time delay in'closing relay 8| isconnected across the busses 5,5 and 56 in series with the contact TI, a normally open contract 820i therelay I6 and a normally closed contact:83 of a relay;84. Anoperating coil .86 of the relay 84 is connected across the busses 55 and 56 in series with a normally'open contact 8'? of the relay 65. The operating coil :80 of the relay =8I :also is connected across the busses 55'and56 in series with the normally open contact 8], =9. normally closed contact .90 of the relay 16 and a normally open contact 9| of the relay 84. An'operating coil '93 of a relay 94 is connected across. the busses '55 and "56 in series with a normally open contact '95 of the relay 8I.

Themotor 33, which operates the inlet valve 32 of the control tank 35, has a terminal 96 connected to the bus 55 m series with a normally open contact 91 oftthe relay 64 and a normally open contact 98'of the relay I6. A terminal 296 of the motor 33 is connected'to the bus 55 in series with a normally open contact I00 of the relay 84. A terminal IOI of the motor 33 is connected directly to the bus 56. The motor 46, which operates the valve 45 connecting the tank and H6 which are connected directly to the bus 55.

When the terminal 96of the motor 33 is connected to the bus 55, the motor is energized to open its associated valve 3 2, and whenxthe terminal 99 connected to the bus 55 the motor is energized to close the valve 32. When the terminal I03 is connected to the bus 55 the mptor 46 is energized to open its associated valve .45, and when the terminal I05 is connected to the bus 56 the motor is energized so as to close the valve 45. When the terminal -I I 0 is connefifiefl to the bus 55 the motor 43 is energized so-as to open its associated valve 4 2, and when the terminal I I I isxconnectecl to the bus 55 the motor 43 isenergized so as to close the valve 4-2.

The probe 46 provided in the receiver {25 connected to a level control device I20, which is similar to the control device 5-? and includes a transformer I2I having primary windings 122-- I22 connected in parallel and across the busses 55 and 56. The probe 148 :isconnected electrically to a terminal I24 of a secondary winding I25 of the transformer, anduthe other terminal of the same secondary winding is grounded at I26. The receiver :25 (Fig. .1) also .isconnected electrically to the ground I26. A secondary winding I21 of the transformer It2I is connected across a rectifier I28 designed'to supply D. C. potential to an operating coil of a relay I3 forming part of the control device I20. An operating coil I33 of a relay I34 is connected across the busses 55 and '56 in series with a normally open contact I35 of then-relay I3I. An alarm device I31, suchas a'horn, a bell, ora'light, is con: nected across the busses 55 and :56 in series with a normally open contact I36 provided on the relay I34. An indicating lamp I45 is connected in parallel with the coil I33 of thelrelay I34.

The control devices 51 and I20 and the probes 36, 31 and 48 are identical in construction and operation, and are designed to effect sequential operation of the valves 3|, 42 and 45 and the alarm I31 in accordance with the level of the condensate in the control tank 35 and in ;the receiver 25. 'While various control devices may b e used, the control devices 5'! and I20 and the .Qperation,

Let it be assumedtthat the reel I0 containing a lengthlofthecableicore.it! 14. S31E5 is positioned in the oven I2, that the door I is closed, that steam is passing through th tubes I l-I4 to raise the temperature of the ovensufiiciently to vaporize the moisture in the paper covering of the cable core and that the motor i? is energized in a conventional manner to drive the vacuum pump I6. The pump I6 draws the gas from the oven I2 and creates a vacuum in the oven, whereby the moisture in the paper vaporizes at a temperature lower than the normal boling point of the moisture. The extracted moisture bearing gas passes through the condenser 2|, the receiver 25 and through the inlet valve 2'! into the pump I6, and discharges the gas through the exhaust valve 28. As the gas extracted from the oven I2 containing the vaporized moisture from the cable passes through the condenser 2|, cold Water circulating through the pipes 22-22 condenses the moisture in the gas. The liquid condensate and the gas pass from the condenser 2| through the pipe 23 to the receiver 25, where the liquid condensate falls to the bottom of the receiver while the gas passes through the pipe 26 into the pump I6. The liquid condensate that collects in the receiver 25 drains by gravity through the normally open valve 30 and flows through the pipe .3I to the valve 32 which is held closed by the motor 33 when the system is placed in operation.

The busses 55 and 56 are energized simultaneously with the starting of the pump I6 so that the control devices 51 and I20 are supplied with a suitable operating potential when the pump starts to extract the gas from the oven I2 and form the condensate in the tank 35. When potential is supplied to the control device 51, it energizes the transformer 60 but the current through the secondary winding 6| is not of sufficient magnitude to energize the relay 65 because the probes 36 and 3'! and the winding 66 are open-circuited. As long as the condensate of the tank 35 does not bridge the probes 36- and 31, the relay 65 remains in its deenergized position in which its normally closed contact I! connects the operating coil 15 of the relay 16 across the busses 55 and 56.

Energization of the coil I5 closes its normally open contacts 02, 98 and I06, and opens its normally closed contact 3|. Closure of the contact 82 connects the operating coil 80 of the time delay relay 8i across the busses in series with the normally closed contact 83 of the relay 84. When the time delay relay 8| completes a predetermined timing cycle,'it closes its normally open contact 95 to energize the operating coil 93 of the relay 34. Energization of the relay 94 closes the normally open contact 91, which connects the terminal 96 of the motor 33 across the busses 55 and 56 in series with the contact 98 previously closed by the energization of the relay 16. Thus, the motor 33 is energized to open its associated valve 32 and allows the condensate to flow from the receiver 25 through the valve 32 into the control tank 35.

Closure of the normally open contact I06 of the relay I6 connects the terminal I05 of the motor 46 and the terminal III of the motor 43 across the busses 55 and 56 prior to the energization of the relay BI and the opening of the inlet valve 32 by the motor 33. Therefore, as soon as potential is supplied to the control device 51, the relay 76 is energized and effects the closure of the drain valve 42 and the vent valve 45 before the relay 8I closes its contact 91 to effect the opening of the inlet valve 32 by the motor 33.

6. The closure of the valves 42 and 45 maintains the system between the oven and the pump air tight, whereby the pump continues to evacuate the'vaporized moisture gas from the oven I 2 and creates a vacuumin the oven I2, the condenser 2|, the receiver 25 and the tank 35. As long as the condensate in the tank 35 does not touch the high-level probe 31, the valves 45 and 42 will remain in their closed positions and the pump continues to evacuate the gas from the oven I2. During this period the oven I2 continues to vaporize the moisture in the insulation of the cable core I I, and the moisture bearing gas withdrawn from the oven I2 continues to pass through the condenser 2| and the condensate from the gas collects in the tank 35.

When the level of the condensate in the controltank 35 reaches the high-level probe 31, the terminal 61 of the secondary winding 66 is connected to ground 10 through the condensat and the probe 31; As a result, both terminals of the winding 66 are grounded, which causes the magnetic field of the transformer 60 to increase to such an extent that the current supplied to the rectifier 62 is sufiicient to energize the operating coil 63 of the relay 65 of the control device51. Energization of the relay .65 closes its normally open contacts I2 and 81 and opens its normally closed contact 1?. Closure of the contact 12 connects the low-level probe 36 to the terminal 61 of the transformer Winding 66, whereby the terminal 61 is maintained at ground potential until the condensate falls below the level of the lowlevel probe 36.

The opening of the normally closed contact 11 disconnects the coil 15 of the relay I6 from the busses 55 and 56, whereupon the relay I6 is deenergized and its contacts 82, 98 and I06 drop open and its contact returns to its normally closed position. The opening of the contact 82 or the relay I6 deenergizes the coil 80 of the relay 8i. Closure of the contact 81 connects the coil 36 of the relay 84 across the busses 55 and 56, whichcloses its normally open contacts 9| and W0 and opens its normally closed contact 83. Closure of the contact I00 connects the terminal 99 of the motor 33 to the bus 55, whereupon the motor 33 is energized so as to close the valve 32 and thereby disconnect the tank 35 from the receiver 25. Closure of the valve 32 stops the flow of thecondensate into the tank 35 and at the same time maintains a vacuum in the system including the oven I2, the condenser 2I and the receiver 25.

Closure of the contact 9| occurs simultaneously with the closure of the contact I00 and connects the operating coil 80 of the time delay relay 6I across the busses 55 and 56 in series with the normally closed contact 00 of the relay 76 and the contact 87 of the relay 65. When the relay BI completes its predetermined timing cycle, which is designed to allow the motor 33 sufficient time to close the valve 32, it closes its normally open contact to connect the operating coil 93 of the relay 94 across the busses 55 and 56. Closure of the contact I04 of the relay 94 connectsthe terminals I03 and H0 of the motors 46 and 43, respectively, to the bus 55 in series with the closed contact I 00 of the relay 84. The motors 43 and 46 then are energized so as to open their respective valves 45 and 42. The open valve 45 connects the control tank 35 to a vent 41, which admits air into the tank, and the open valve 42 permits the condensate to drain from the control tank 35into the drain pipe 40.

As? long. as the low level probe 36 contacts the condensate in the tank 35 the transformer winding 6.6 has. .bothterminals thereof connected'to ground ID and the transformer El maintains the coil 6.3. energized. As the condensate drains from the tank 35 and falls below the level of the probe 36, the terminal 61 of the transformer is disconnected from ground Ill. The removal of the terminal 61' from. ground potential reduces the magnetic field of the transformer 6.0 so that the winding GI no longer provides sufficient current to the rectifier I52 to energize the coil 63'. As a result, the coil 63 is deenergized. and its contacts 12 and 81 drop open and its contact 17 returns to its normally closed position.

When the level of the condensate in the tank. 35causes the relay 6.3 to be deenergizedin this manner, the opening of the contact 81 deenergizes. the relays 84, 8| and. 94 in that order, whereupon their respective contacts return to their deenergized positions shown in the diagram. The reclosing, of the contact I.-I' energizes the relay I5, which in turn effects. the sequential. energization of the time delay relay 8| and the relay 94 in the manner described hereinabove. Closure of the contact 98 f the relay 16 connects the terminals I and III of the motors 46 and 43, respectively, to the. bus 55, whereupon the motors are energized so as to close their respective valves 45 and 42. Some time. after the valves 45 and 42 are closed-, the time delay relay- 83I completes its timing period and closes its normally open; contact 35 to energize the coil 93 of the relay 94. Energization of the relay 94 closes its; contacts: (and I04. However, only the closure of. the contact 91 is effective at this point,v and'it connects the terminal of the motor 33, to the bus 55. in series with the contact 98 of the relay 15.. The motor: 33: now is energized so as to open itsassociated valve 32, whereupon the condensate collected in the. receiver 25 and pipe 3.! while the condensate was draining; from. the control tank 35,-, flows from the receiver 25 through the Valves 30 and: 32 into the control.

tank.

Since the valve. 45 which connects the vent. 41' to the control tankv 3-5; andthe drain valve 42. are. closed before thevalve32 is opened bythe motor 33, the opening of; the valve 32does'not. affect the vacuumin the, oven I2, the; condenser Z I, and receiver 25 exceptjfor the. small amount, of air admitted into the control tank 35- when. the condensate was draining into the pipe, 40. The operation of the valves 32, 42 and 45 in the? abovedescribed sequence' permits the condensate to be drained from the tank 35- while. the pump is operating to extract the vaporized moisture gas from the oven I2.

The pump continues to operate, and" the condensate collects in the control tank 35 until it reaches the high-levelprobe 31. At this point the valve 32 is closed: and. the. valves. 42 and 45 are open in the above-described sequence to drain. the condensate'irorn the, tank. This pro.

cedure is carriedout. by the control device 51- 65 in conjunction. with. the. probes. 3:6 and 3T throughout the entire opera-ting period of; the; pump in extracting; themoisture, from. the. cable core I I.

If thecontroldevicetil should'failto drain the 7 control tank 35; in;th,e manner: described, the. condensate wouldfill. the; controltank and even.- tually. would eta-rote fill. the; receiver 25; to such a point thatsomaof thecondensatermight gas'from the receiver 25.. :If such a condition should occur, the presence of the liquid condensate in the pump would result in serious damage in the pump and to the motor H. To prevent such a condition from; 'ocouring, the probe 48 is mounted in the receiver 25 and is connected electrically to the control device I20 so as to actuate the alarm I31 and light the lamp I40 when the level of the condensate reaches the probe 48. As long as the condensate in the receiver 25 does not reach the probe 48, the secondary winding I22 is open-circuited and keeps the secondary winding I21 from generating sufficient current to energize the coil I of the relay I3I. As a result, the normally open con tact I remains open and the relay I34 remains deenergized.

However, if the condensate collected in the receiver 25 reaches the level of the probe 48, the terminal I24 of the transformer winding I22 is connected to ground through. a circuit including the probe 48 and the condensate in the receiver. When the terminal I2 3 of the transformer is grounded it causes the winding I21 to generate sufficient current through the rectifier i28 to energize the coil I30 of the relay I-3l. Energization of the relay I3I closes its normally open'contact I35 and connects the coil I33 of the relay I34 across the busses. Closure of the contact I35 also connects an indicating lamp I across the busses to indicate that the level control device 51 is not functioning and that the condensate has reached the probe 58 positioned in the receiver 25.

Energization of the relay I34 closes its normally open contact I38, which connects the signal device I31 across the busses to. announce the fact that the vacuum system should be shut down before the condensate reaches such a level in the receiver 25 that it will be drawn into the pump ing liquids from various types of vacuum systems without departing from the spirit and scope of ticle. and means for condensing the moisture in the extracted gas as it travels from the vessel to the pump, the improvement which comprises means normally communicating. with the vessel for collecting the condensate so produced, a detector sensitive to changes in the level of the: condensate within the collecting means, means. actuated by the detector for disconnecting. the condensate collecting means from the vessel when the condensate reaches a predetermined high levelin the oollectingmeans, means actuated by when the. condensate within the collecting means reaches a predetermined lower level for closing the; collecting means to the atmosphere to terminate the draining of the condensate therefrom and; for reconnecting the: collecting means tothe vessel; whereby the condensate mayagain collect he ucked. into the pump: I16 w th the extracted 7,5: withinthe. collecting means.

2. Apparatus for discharging fluids from a vacuum system including a vessel designed to receive a moisture bearing article and a vacuum pump for extracting moisture laden gas from the article, which comprises means connected to the vessel for condensing any moisture in the extracted gas as the gas travels from the vessel to the pump, means connected to the condensing means and to the pump for separating the resulting condensate from the extracted gas, means connected to the separating means for collecting a resulting condensate, a detector sensitive to changes in the level of the condensate within the collecting means, means actuated by the detector when the condensate within the collecting means reaches a predetermined high level to disconnect said collecting means from the vessel, means actuated by the detector for automatically opening the collecting means to the atmosphere a predetermined time interval after the collecting means is disconnected from the vessel to drain the condensate therefrom, and means actuated by the detector when the condensate within the collecting means reaches a predetermined lower level to close the collecting means so as to terminate the draining of the condensate therefrom and to reconnect the collecting means to the vessel whereby the condensate may again collect within the collecting means.

3. Apparatus for discharging fluids from a vacuum system including a vessel designed to receive a moisture bearing article and a pump for extracting moisture laden gas from the vessel, which comprises means connected to the vessel for condensing any moisture in the gas extracted from the vessel as the gas travels from the vessel to the pump, means connected to the condensing means and to the pump for separating the resulting condensate from the gas, a tank for collecting the condensate, a conduit connectin the tank to the separating means, a motor-operated, normally open valve located in said conduit, a vent communicating with the tank, a second motor-operated, normally closed valve located in the vent, a drain communicating with the lower end of said tank, a third motor-operated, normally closed valve located in the drain, a, detector sensitive to changes in the level of the condensate within the tank, means actuated by the detector for operatin the valve in the conduit to disconnect the tank from the separating means when the condensate within the tank reaches a predetermined high level, means actuated by the detector a predetermined time interval after the tank is disconnected from the separating means for opening the valve in the vent whereby the tank is connected through the vent to the atmosphere, means actuated by the detector when valve in the vent is opened for actuating the val c in the drain to discharge the condensate which has collected within the tank, means actuated by the detector for closing the valve in the drain when the condensate within the tank has reached a predetermined lower level to terminate the draining of the condensate from the tank, and means actuated when the valve in the drain has been reclosed to' sequentially close the valve in the vent and open the valve in the conduit to reconnect the tank to the separating means.

4. Apparatus for discharging fluids from a vacuum system including a vessel designed to receive a moisture bearing article and a vacuum pump for extracting moisture laden gas from the article, which comprises means connected to the vessel for condensing any moisture in the extracted gas as the gas travels from the vessel to the pump, means connected to the condensing means and to the pump for separating the resulting condensate from the extracted gas, a tank for collecting the condensate, a conduit connecting said tank to the separating means, a drain provided in the tank, a detector sensitive to the level of the condensate within the tank, a motor-driven valve located in the conduit actuated by the detecting means when the condensate within the tank reaches a predetermined high level to disconnect the tank from the separating means, a motordriven exhaust valve actuated by the detector a predetermined time interval after the tank has been disconnected from the separating means to open the tank to the atmosphere, a motor-driven drain valve actuated by the detector after the exhaust valve has been operated to open the drain in the tank to allow the condensate to be evacuated therefrom, means actuated by the detector to close the drain valve when the condensate within the tank reaches a predetermined lower level and to close the exhaust valve, and means actuated by the detector, when the drain valve and exhaust valve have been closed, to open the valve in the conduit to reconnect the tank to the separating means, whereby the condensate may again collect within the tank.

EDGAR W. HERTENSTEIN, JR.

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